Stand up urgency: is this symptom related to a urethral mechanism?

OBJECTIVE To study the role of women's position as a stimulus of urgency, and specifically the change of position, i.e. to stand up form a lying or sitting position. Thus, we compared clinical and urodynamics characteristics among women with overactive bladder syndrome (OAB) depending of the position which could trigger urgency. METHODS Thirty-eight females with complaints of urgency, without urinary infection, neurological or urological diseases, were prospectively enrolled. Patients completed a study-specific questionnaire asking about urgency and urge incontinence when in three different positions (standing up, sitting, and standing position). We named stand up urgency (SUU) an urgency, which was defined thanks to this questionnaire, according to the presence of urgency triggered by the change from sitting or lying to a standing position. All patients underwent cystometry in the standing position, urethral closure pressure measurement (MUCP) and Valsalva leak point pressure (VLPP) tests. Urodynamics characteristics were compared in the groups defined by the questionnaire. RESULTS SUU was associated with lower MUCP (57 vs. 77 cm H(2)O; P=0.017), but not with positive VLPP or DO. Among females with SUU, those with stand up urge incontinence (SUUI) also had lower MUCP (46 vs. 73 cm H(2)O; P=0.019) and more positive cough stress tests (73 vs. 13%; P=0.019). Conversely, urge incontinence in the sitting position was associated with DO (46% vs. 0%; P=0.02), but not with lower MUCP or positive VLPP. CONCLUSION SUU appeared to be related to impaired urethral closure mechanisms (lower MUCP), but future studies are needed to confirm this hypothesis.